Process for preparing a supported polymerization catalyst using reduced amounts of solvent and polymerization process

ABSTRACT

The subject invention provides a process for preparing an olefin polymerization catalyst wherein a calcined and passivated silica support (support precursor) is sequentially contacted with a first solution of a metal complex or of a cocatalyst, and thereafter with a second solution of the other of the metal complex or the cocatalyst, wherein the second solution is provided in an amount such that 100 percent of the pore volume of the support precursor is not exceeded. Optionally, the compatible solvent of the first and/or second solutions is removed. The subject invention further provides a process for polymerizing one or more α-olefins in the presence of the olefin polymerization catalyst prepared by the process of the invention.

Claims the benefit of U.S. Provisional application No. 60/114,372, filedDec. 30, 1998.

The subject invention is directed to a process for supporting a singlesite metallocene or constrained geometry catalyst and cocatalyst; to thesupported catalyst systems resulting therefrom; and to a process forpolymerizing at least one α-olefin utilizing the supported catalystsystem of the invention.

Olefin polymerization catalysts used in the fluidized gas phase processare typically supported on a carrier to impart the necessary particlemorphology to the polymer powder. A preferred method of supporting highactivity single site constrained geometry or metallocene catalysts andproducing a powder involves preparing a solvent mixture of the supportand the catalyst/cocatalyst components and removing the solvent underheat and vacuum. However, such a method poses preparation/stabilityconcerns, as well as polymer product morphology concerns.

In terms of the preparation/stability concerns, once the catalyst andcocatalyst components are mixed at an elevated activating temperature,they are not typically stable for an indefinite period of time, eitheras a solution or as deposited on treated silica. Subsequent work up ofthe catalyst often requires one or more solvent washes, solvent decants,and/or filtrations, followed by the removal the solvent, typically byapplication of heat and vacuum. However, exposure to elevatedtemperatures, long drying times, and/or incomplete removal of solventcan often have a deleterious effect on, catalyst activity, either duringpreparation or upon storage. Further, the volume of solvent required tomake a flowable slurry is typically at least 4 L/Kg of catalyst powder.A catalyst formulation technique that minimizes the amount of solventrequired for preparation would be advantageous.

In terms of the product morphology concerns, when a single site catalystis activated by a suitable cocatalyst prior to introduction into thereactor, the catalyst is at peak activity when injected into thereactor. This can result in sudden and intense activity, severefracturing of the catalyst particles leading to high fines, and/or highexotherms leading to agglomerates. In addition, fouling of the catalystinjection system can occur.

It is noted that traditional Ziegler-Natta catalysts do not achieve peakactivity until after the catalyst has been injected into the reactor.This may be in part attributed to the fact that, in the case of typicalZiegler-Natta polymerization processes, addition of Et₃Al to the reactorcan result in metal activation. See, for instance, Boor, John Jr.,Ziegler-Natta Catalysts and Polymerizations, 1979, Academic Press. NY,Chapter 18: Kinetics.

To control the polymerization of at least one α-olefin by a single siteconstrained geometry or metallocene catalyst in a gas phasepolymerization process, an in-reactor activation of metal sites on thecarrier would be advantageous. However, this is not without difficulty.Typical single site constrained geometry and metallocene catalystcomponents, and activators for such catalyst components, such as methylalumoxane and fluorinated aryl boranes and borates have low vaporpressures, making dual injection difficult.

U.S. Pat. No. 5,332,706 discloses a process for preparing a supportedcatalyst, comprising applying an alumoxane solution to a porous support,such that alumoxane solution is provided to the support in an amountinsufficient to form a slurry thereof. The application contemplatesadding a metallocene to the alumoxane solution prior to contacting withthe support.

U.S. Pat. No. 5,625,015 discloses a process for preparing a supportedcatalyst, comprising spraying a solution of the catalyst and cocatalystonto a support, wherein the solution is provided in such an amount thatthe pore volume of the support is exceeded.

U.S. Pat. No. 5,721,184 discloses a process for preparing a supportedcatalyst, comprising spraying a solution of the catalyst & cocatalystonto a support disposed in a conical dryer. The application contemplatesembodiments wherein the volume of catalyst solution is less than thepore volume of the support.

PCT Application WO 97/02297 discloses a method for forming aprepolymerized supported metallocene catalyst system, comprisingprepolymerizing a gaseous olefin monomer in the presence of a supportedmetallocene catalyst system wherein the pores of the catalyst systemcontain a volume of liquid equal to or less than the total pore volumeof the supported catalyst system.

PCT Application WO 97/29134 discloses a process for making a supportedmetallocene/alumoxane catalyst system. One embodiment contemplatesadding solutions of metallocene and alumoxane separately to the support,where the solution has a total volume in the range of from two to threetimes the total pore volume of the support.

U.S. Pat. No. 5,422,325 discloses a process for making a supportedcatalyst system comprising slurrying a support in a solvent, andsequentially adding to the slurry a solution of a metallocene catalystand a solution of an alumoxane cocatalyst. The disclosed process employsa drying step after the addition of both solutions is complete.

Industry would find great advantage in a supported catalyst formulationthat is robust, has a delayed activity indicating extended shelf life,and is useful to polymerize α-olefins to form polymer particles havinglow fines (<125 μm), low agglomerates (>1500 μm), and an acceptable bulkdensity (>0.3 g/mL).

Accordingly, the present invention is directed to a process forformulating a supported olefin polymerization catalyst that does notrequire exposure to excessive heat during any solvent removal steps, andwhich exhibits robust activity despite a delay between the preparationof the supported catalyst system and its introduction into apolymerization reactor.

The subject invention further provides a process for preparing supportedcatalyst systems that exhibit a decreased rate of catalyst activation atroom temperature.

In particular, the subject invention provides a process for preparing anolefin polymerization catalyst comprising:

-   -   A. calcining silica at a temperature of 30 to 1000° C. to form        calcined silica,    -   B. reacting the calcined silica with an agent selected from the        group consisting of:        -   i. Lewis acid alkylating agents,        -   ii. silane or chlorosilane functionalizing agents, and        -   iii. aluminum components selected from an alum xane or an            aluminum compound of the formula AIR¹ _(x′)R² _(y′), wherein            R¹ independently each occurrence is hydride or R, R² is            hydride, R or OR, x′ is 2 or 3, y′is 0 or 1 and the sum of            x′ and y′ is 3,        -   to form a support precursor having a specified pore volume,    -   C. applying to the support precursor a first solution in a        compatible solvent of one of the following:        -   (1) a complex of a metal of Groups 3-10 of the Periodic            Table of the Elements or        -   (2) a cocatalyst selected from the group consisting of            non-polymeric, non-oligomeric complexes capable of            activating the complex of (C)(i) for the polymerization of            o-olefins        -   and optionally removing the compatible solvent to form a            supported procatalyst;    -   D. applying to the supported procatalyst a second solution in a        compatible solvent of the other of the catalyst or cocatalyst        of (C) to form a supported catalyst, wherein the second solution        is provided in an amount such that 100 percent of the pore        volume of the support precursor is not exceeded; and    -   E. optionally removing the compatible solvent from the supported        catalyst to form a recovered supported catalyst system.

The subject invention further provides a process for polymerizing atleast one α-olefin monomer comprising:

-   -   A. preparing a supported cocatalyst by:        -   i. calcining silica at a temperature of 30 to 1000° C. to            form calcined silica,        -   ii. reacting the calcined silica with an agent selected from            the group consisting of:            -   (a) Lewis acid alkylating agents,            -   (b) silane or chlorosilane functionalizing agents, and            -   (c) aluminum components selected from an alumoxane or an                aluminum compound of the formula AIR¹ _(x′)R² _(y′),                wherein R¹ independently each occurrence is hydride or                R, R² is hydride, R or OR, x′ is 2 or 3, y′ is 0 or 1                and the sum of x′ and y′ is 3,            -   to form a support precursor having a specified pore                volume,        -   iii. applying to the support precursor a first solution in a            compatible solvent of one of the following:            -   (a) a complex of a metal of Groups 3-10 of the Periodic                Table of the Elements or            -   (b) a cocatalyst selected from the group consisting of                non-polymeric, non-oligomeric complexes capable of                activating the complex of (C)(i) for the polymerization                of α-olefins            -   and optionally removing the compatible solvent to form a                supported procatalyst;        -   iv. applying to the recovered supported procatalyst a second            solution in a compatible solvent of the other of the            catalyst or cocatalyst of (C) to form a supported catalyst,            wherein the second solution is provided in an amount such            that 100 percent of the pore volume of the support precursor            is not exceeded; and        -   v. optionally removing the compatible solvent from the            supported catalyst to form a recovered supported catalyst            system;    -   B. pressurizing a gas phase polymerization reactor with the at        least one α-olefin monomer to be polymerized;    -   C. introducing the recovered supported catalyst system to the        gas phase polymerization reactor;    -   D. activating the recovered supported catalyst system; and    -   E. recovering the polymerized product from the reactor.

These and other embodiments are more fully described in the followingdetailed description.

The supported catalyst systems of the invention will comprise a metalcomplex, a cocatalyst, and a support.

Concerning the Metal Complex

Suitable metal complexes for use in the practice of the claimedinvention include any complex of a metal of Groups 3-10 of the PeriodicTable of the Elements capable of being activated to polymerize additionpolymerizable compounds, especially olefins.

Suitable metal complexes may be derivatives of any transition metalIncluding Lanthanides, but preferably of Group 3, 4; or Lanthanidemetals which are in the +2, +3, or +4 formal oxidation state meeting thepreviously mentioned requirements. Preferred compounds include metalcomplexes (metallocenes) containing from 1 to 3 π-bonded anionic ligandgroups, which may be cyclic or noncyclic delocalized π-bonded anionicligand groups. Exemplary of such π-bonded anionic ligand groups areconjugated or nonconjugated, cyclic or non-cyclic dienyl groups, allylgroups, and arene groups. By the term “π-bonded” is meant that theligand group is bonded to the transition metal by means of delocalizedelectrons present in a π bond.

Each atom in the delocalized π-bonded group may independently besubstituted with a radical selected from the group consisting ofhalogen, hydrocarbyl, halohydrocarbyl, and hydrocarbyl-substituted Group14 or 15 radicals. Included within the term “hydrocarbyl” are C₁₋₂₀straight, branched and cyclic alkyl radicals, C₆₋₂₀ aromatic radicals,C₇₋₂₀ alkyl-substituted aromatic radicals, and C₇₋₂₀ aryl-substitutedalkyl radicals. In addition two or more such radicals may together forma fused ring system or a hydrogenated fused ring system. Suitablehydrocarbyl-substituted Group 14 or 15 radicals include mono-, di- andtrihydrocarbyl-substituted radicals of Group 14 or 15 elements whereineach of the hydrocarbyl groups contains from 1 to 20 carbon atoms or twosuch groups together form a divalent derivative thereof. Examples ofsuitable hydrocarbyl-substituted Group 14 or 15 radicals includetrimethylsilyl, triethylsilyl, ethyldimethylsilyl, methyldiethylsilyl,triphenylgermyl, trimethylgermyl, dimethylamino, dimethylphosphino, and1-pyrrolidinyl groups.

Examples of suitable anionic, delocalized π-bonded groups includecyclopentadienyl, indenyl, fluorenyl, tetrahydroindenyl,tetrahydrofluorenyl, octahydrofluorenyl, pentadienyl, cyclohexadienyl,dihydroanthracenyl, hexahydroanthracenyl, and decahydroanthracenylgroups, as well as C₁₋₁₀ hydrocarbyl-substituted derivatives thereof.Preferred anionic delocalized π-bonded groups are cyclopentadienyl,pentamethylcyclopentadienyl, tetramethylcyclopentadienyl, indenyl,2,3-dimethylindenyl, fluorenyl, 2-methylindenyl and2-methyl-4-phenylindenyl.

More preferred are metal complexes corresponding to the formula:L_(l)MX_(m)X′_(n)X″_(p), or a dimer thereof

-   -   wherein:    -   L is an anionic, delocalized, π-bonded group that is bound to M,        containing up to 50 nonhydrogen atoms, optionally two L groups        may be joined together through one or more substituents thereby        forming a bridged structure, and further optionally one L may be        bound to X through one or more substituents of L;    -   M is a metal of Group 4 of the Periodic Table of the Elements in        the +2, +3 or +4 formal oxidation state;    -   X is an optional, divalent substituent of up to 50 non-hydrogen        atoms that together with L forms a metallocycle with M;    -   X′ is an optional neutral Lewis base having up to 20        non-hydrogen atoms;    -   X″ each occurrence is a monovalent, anionic moiety having up to        40 non-hydrogen atoms, optionally, two X″ groups may be        covalently bound together forming a divalent dianionic moiety        having both valences bound to M, or form a neutral, conjugated        or nonconjugated diene that is π-bonded to M (whereupon M is in        the +2 oxidation state), or further optionally one or more X″        and one or more X′ groups may be bonded together thereby forming        a moiety that is both covalently bound to M and coordinated        thereto by means of Lewis base functionality;    -   l is 1 or 2;    -   m is 0 or 1;    -   n is a number from 0 to 3;    -   p is an integer from 0 to 3; and    -   the sum, l+m+p, is equal to the formal oxidation state of M.

Such preferred complexes include those containing either one or two Lgroups. The latter complexes include those containing a bridging grouplinking the two L groups. Preferred bridging groups are thosecorresponding to the formula (ER*₂)_(x) wherein E is silicon or carbon,R* independently each occurrence is hydrogen or a group selected fromsilyl, hydrocarbyl, hydrocarbyloxy and combinations thereof, said R*having up to 30 carbon or silicon atoms, and x is 1 to 8. Preferably, R*independently each occurrence is methyl, benzyl, tert-butyl or phenyl.

Examples of the foregoing bis(L) containing complexes are compoundscorresponding to the formula:

wherein:

-   -   M is titanium, zirconium or hafnium, preferably zirconium or        hafnium, in the +2 or +4 formal oxidation state;    -   R³ in each occurrence independently is selected from the group        consisting of hydrogen, hydrocarbyl, silyl, germyl, cyano, halo        and combinations thereof, said R³ having up to 20 non-hydrogen        atoms, or adjacent R³ groups together form a divalent derivative        (that is, a hydrocarbadiyl, siladiyl or germadiyl group) thereby        forming a fused ring system, and    -   X″ independently each occurrence is an anionic ligand group of        up to 40 nonhydrogen atoms, or two X″ groups together form a        divalent anionic ligand group of up to 40 nonhydrogen atoms or        together are a conjugated diene having from 4 to 30 non-hydrogen        atoms forming a x-complex with M, whereupon M is in the +2        formal oxidation state, and    -   R*, E and x are as previously defined.

The foregoing metal complexes are especially suited for the preparationof polymers having stereoregular molecular structure. In such capacityit is preferred that the complex possess C₂ symmetry or possess achiral, stereorigid structure. Examples of the first type are compoundspossessing different delocalized π-bonded systems, such as onecyclopentadienyl group and one fluorenyl group. Similar systems based onTI(IV) or Zr(IV) were disclosed for preparation of syndiotactic olefinpolymers in Ewen, et al., J. Am. Chem. Soc. 110, 6255-6256 (1980).Examples of chiral structures include bis-indenyl complexes. Similarsystems based on TI(IV) or Zr(IV) were disclosed for preparation ofisotactic olefin polymers in Wild et al., J. Organomet. Chem, 232,233-47, (1982).

Exemplary bridged ligands containing two n-bonded groups are:(dimethylsilyl-bis-cyclopentadienyl),(dimethylsilyl-bis-methylcyclopentadienyl),(dimethylsilyl-bis-ethylcyclopentadienyl,(dimethylsilyl-bis-1-butylcyclopentadienyl),(dimethylsilyl-bis-tetramethylcyclopentadienyl),(dimethylsilyl-bis-indenyl), (dimethylsilyl-bis-tetrahydroindenyl),(dimethylsilyl-bis-fluorenyl), (dimethylsilyl-bis-tetrahydrofluorenyl),(dimethylsilyl-bis-2-methyl-4-phenylindenyl),(dimethylsilyl-bis-2-methylindenyl),(dimethylsilyl-cyclopentadienyl-fluorenyl), (1, 1, 2,2-tetramethyl-1,2-disilyl-bis-cyclopentadienyl),(1,2-bis(cyclopentadienyl)ethane, and(isopropylidene-cyclopentadienyl-fluorenyl).

Preferred X″ groups are selected from hydride, hydrocarbyl, silyl,germyl, halohydrocarbyl, halosilyl, silylhydrocarbyl andaminohydrocarbyl groups, or two X″ groups together form a divalentderivative of a conjugated diene or else together they form a neutral,π-bonded, conjugated diene. Most preferred X″ groups are C₁₋₂₀hydrocarbyl groups.

A further class of metal complexes utilized in the present inventioncorrespond to the formula:L_(l)MX_(m) ^(X′) _(n)X″_(p), or a dimer thereof

-   -   wherein:    -   L is an anionic, delocalized, π-bonded group that is bound to M,        containing up to 50 nonhydrogen atoms;    -   M is a metal of Group 4 of the Periodic Table of the Elements in        the +2, +3 or +4 formal oxidation state;    -   X is a divalent substituent of up to 50 non-hydrogen atoms that        together with L forms a metallocycle with M;    -   X′ is an optional neutral Lewis base ligand having up to 20        non-hydrogen atoms;    -   X″ each occurrence is a monovalent, anionic moiety having up to        20 non-hydrogen atoms, optionally two X″ groups together may        form a divalent anionic moiety having both valences bound to M        or a neutral C₅₋₃₀ conjugated diene, and further optionally X′        and X″ may be bonded together thereby forming a moiety that is        both covalently bound to M and coordinated thereto by means of        Lewis base functionality;    -   l is 1 or 2;    -   m is 1;    -   n is a number from 0 to 3;    -   p is an integer from 1 to 2; and    -   the sum, l+m+p, is equal to the formal oxidation state of M.

Preferred divalent X substituents preferably include groups containingup to 30 nonhydrogen atoms comprising at least one atom that is oxygen,sulfur, boron or a member of Group 14 of the Periodic Table of theElements directly attached to the delocalized π-bonded group, and adifferent atom, selected from the group consisting of nitrogen,phosphorus, oxygen or sulfur that is covalently bonded to M.

A preferred class of such Group 4 metal coordination complexes usedaccording to the present invention correspond to the formula:

-   -   wherein:    -   M is titanium or zirconium in the +2 or +4 formal oxidation        state;    -   R³ in each occurrence independently is selected from the group        consisting of hydrogen, hydrocarbyl, silyl, germyl, cyano, halo        and combinations thereof, said R³ having up to 20 non-hydrogen        atoms, or adjacent R³ groups together form a divalent derivative        (that is, a hydrocarbadiyl, siladiyl or germadiyl group) thereby        forming a fused ring system,    -   each X″ is a halo, hydrocarbyl, hydrocarbyloxy or silyl group,        said group having up to 20 nonhydrogen atoms, or two X″ groups        together form a C₅₋₃₀ conjugated diene;    -   Y is —O—, —S—, —NR*—, —PR*—; and    -   Z is SiR*₂, CR*₂, SiR₁₂SiR₁₂, CR*₂CR*₂, CR*═CR*, CR*₁₂SiR₂, or        GeR*₂, wherein: R* is as previously defined.

A further class of metal complexes useful in preparing the catalysts ofthe invention include Group 10 dilmine derivatives corresponding to theformula:

-   -   CT—CT is 1,2-ethanediyl, 2,3-butanediyl, or form a fused ring        system wherein the two T groups together are a 1,8-naphthanediyl        group; and    -   A′ is the anionic component of the foregoing charge separated        activators.

Similar complexes to the foregoing are also disclosed by M. Brookhart,et al., in J. Am. Chem. Soc., 118, 267-268 (1996) and J. Am. Chem. Soc.,117, 6414-6415 (1995), as being active polymerization catalystsespecially for polymerization of α-olefins, either alone or incombination with polar comonomers such as vinyl chloride, alkylacrylates and alkyl methacrylates.

Additional complexes include derivatives of Group 3, 4, or Lanthanidemetals containing from 1 to 3 π-bonded anionic or neutral ligand groups,which may be cyclic or non-cyclic delocalized π-bonded anionic ligandgroups. Exemplary of such π-bonded anionic ligand groups are conjugatedor nonconjugated, cyclic or non-cyclic dienyl groups, allyl groups,boratabenzene groups, and arene groups. By the term “π-bonded” is meantthat the ligand group is bonded to the transition metal by a sharing ofelectrons from a partially delocalized π-bond.

Each atom in the delocalized π-bonded group may independently besubstituted with a radical selected from the group consisting ofhydrogen, halogen, hydrocarbyl, halohydrocarbyl, hydrocarbyloxy,hydrocarbylsulfide, dihydrocarbylamino, and hydrocarbyl-substitutedmetalloid radicals wherein the metalloid is selected from Group 14 ofthe Periodic Table of the Elements, and such hydrocarbyl-,halohydrocaryl-, hydrocarbyloxy-, hydrocartylsulfide-,dihydrocarbylamino- or hydrocarbyl-substituted metalloid radicals thatare further substituted with a Group 15 or 16 hetero ator containingmoiety. Included within the term “hydrocarbyl” are C₁₋₂₀ straight,branched and cyclic alkyl radicals, C₆₋₂₀ aromatic radicals, C₇₋₂₀alkyl-substituted aromatic radicals, and C₇₋₂₀ aryl-substituted alkylradicals. In addition two or more such radicals may together form afused ring system, including partially or fully hydrogenated fused ringsystems, or they may form a metallocycle with the metal. Suitablehydrocarbyl-substituted organometalloid radicals include mono-, di- andtri-substituted organometalloid radicals of Group 14 elements whereineach of the hydrocarbyl groups contains from 1 to 20 carbon atoms.Examples of suitable hydrocarbyl-substituted organo-metalloid radicalsinclude trimethylsilyl, triethylsilyl, ethyldimethylsilyl,methyldiethyl-silyl, triphenylgermyl, and trimethylgermyl groups.Examples of Group 15 or 16 hetero atom containing moieties includeamine, phosphine, ether or thioether moieties or divalent derivativesthereof, for example, amide, phosphide, ether or thioether groups bondedto the transition metal or Lanthanide metal, and bonded to thehydrocarbyl group or to the hydrocarbyl-substituted metalloid containinggroup.

Examples of suitable anionic, delocalized 7-bonded groups includecyclopentadienyl, indenyl, fluorenyl, tetrahydroindenyl,tetrahydrofluorenyl, octahydrofluorenyl, pentadienyl, cyclohexadienyl,dihydroanthracenyl, hexahydroanthracenyl, decahydroanthracenyl groups,and boratabenzene groups, as well as C₁₋₁₀ hydrocarbyl-substituted,C₁₋₁₀ hydrocarbyloxy-substituted, di(C₁₋₁₀hydrocarbyl)amino-substituted, or tri (C₁₋₁₀hydrocarbyl)silyl-substituted derivatives thereof. Preferred anionicdelocalized n-bonded groups are cyclopentadienyl,pentamethylcyclopentadienyl, tetramethylcyclopentadienyl,tetramethylsilylcyclo-pentadienyl, indenyl, 2,3-dimethylindenyl,fluorenyl, 2-methylindenyl, 2-methyl-4-phenylindenyl,tetrahydrofluorenyl, octahydrofluorenyl, and tetrahydroindenyl.

The boratabenzenes are anionic ligands which are boron containinganalogues to benzene. They are previously known in the art having beendescribed by G. Herberich, et al., in Organometallics, 1995, 14, 1,471-480. Preferred boratabenzenes correspond to the formula:

-   -   wherein R″ is selected from the group consisting of hydrocarbyl,        silyl, or germyl, said R″ having up to 20 non-hydrogen atoms. In        complexes involving divalent derivatives of such delocalized        π-bonded groups one atom thereof is bonded by means of a        covalent bond or a covalently bonded divalent group to another        atom of the complex thereby forming a bridged system.

Illustrative Group 4 metal complexes that may be employed in thepractice of the present invention include:

-   cyclopentadienyltitaniumtrimethyl,-   cyclopentadienyltitaniumtriethyl,-   cyclopentadienyltitaniumtrisopropyl,-   cyclopentadienyltitaniumtriphenyl,-   cyclopentadienyltitaniumtribenzyl,-   cyclopentadienyltitanium-2,4-pentadienyl,-   cyclopentadienyltitaniumdimethylmethoxide,-   cyclopentadienyltitaniumdimethylchloride,-   pentamethylcyclopenladienyltitaniumtrimethyl,-   indenyltitaniumtrlmethyl,-   indenyltitaniumtriethyl,-   indenyltitaniumtripropyl,-   indenyltitaniumtriphenyl,-   tetrahydroindenyltitaniumtribenzyl,-   pentamethylcyclopentadienyltitaniumtriisopropyl,-   pentamethylcyclopentadienyltitaniumtribenzyl,-   pentamethylcyclopentadienyltitaniumdimethylmethoxide,-   pentamethylcyclopentadienyltitaniumdimethylchloride,-   (η⁵-2,4-dimethyl-1,3-pentadienyl)titaniumtrimethyl,-   octahydrofluorenyltitaniumtrimethyl,-   tetrahydroindenyltitaniumtrimethyl,-   tetrahydrofluorenyltitaniumtrimethyl,-   (1,1-dimethyl-2,3,4,9,10-η⁵-1,4,5,6,7,8-hexahydronaphthalenyl)titaniumtrimethyl,    (1,1,2,3-tetramethyl-2,3,4,9,10-η⁵-1,4,5,6,7,8-hexahydronaphthalenyl)titaniumtrimethyl,-   (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)    dimethylsilanetitanium dichloride,-   (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium    dimethyl,-   (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyltitanium    dimethyl,-   (tert-butylamido)(hexamethyl-η⁵-indenyl)dimethylsilanetitanium    dimethyl,-   (tert-butylamido)(tetramethyl-η⁵-cycopentadienyl)dimethylsilane    titanium (III) 2-(dimethylamino)benzyl;-   (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium (III)    allyl,-   (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium (II)    1,4-diphenyl-1,3-butadiene,-   (tert-butylamido)(2-methylindenyl)dimethylsilanetitanium(II)    4-diphenyl-1,3-butadiene,-   (tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (IV)    1,3-butadiene,-   (tert-butylamido)(2,3-dimethylindenyl)dimethylsilanetitanium (II)    1,4-diphenyl-1,3-butadiene,-   (tert-butylamido)(2,3-dimethylindenyl)dimethylsilanetitanium (IV)    1,3-butadiene,-   (tert-butylamido)(2,3-dimethylindenyl)dimethylsilanetitanium (II)    1,3-pentadiene,-   (tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (II)    1,3-pentadiene,-   (tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (IV)    dimethyl,-   (tert-butylamido)(2-methyl-4-phenylindenyl)dimethylsilanetitanium (II)    1,4-diphenyl-1,3-butadiene,-   (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium (IV)    1,3-butadiene,-   (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium    (II)1,4-dibenzyl-1,3-butadiene,-   (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium (II)    2,4-hexadiene,-   (tert-butylamido)(tetramethyl-(5-cyclopentadienyl)dimethylsilanetitanium (II)    3-methyl 1,3-pentadiene,-   (tert-butylamido)(2,4-dimethyl-1,3-pentadien-2-yl)dimethylsilanetitaniumdimethyl,-   (tert-butylamido)(1,1-dimethyl-2,3,4,9,10-η⁵-1,4,5,6,7,8-hexahydronaphthalen-4-yl)dimethylsilanetitaniumdimethyl,-   (tert-butylamido)(1,1,2,3-tetramethyl-2,3,4,9,10-η⁵-1,4,5,6,7,8-hexahydronaphthalen-4-yl)dimethylsilanetitaniumdimethyl,-   (tert-butylamido)(tetramethylcyclopentadienyl)dimethylsilanetitanium    1,3-pentadiene,-   (tert-butylamido)(3-(N-pyrrolidinyl)inden-1-yl)dimethylsilanetitanium    1,3-pentadiene,-   (tert-butylamido)(2-methyl-s-indacen-1-yl)dimethylsilanetitanium    1,3-pentadiene, and-   (tert-butylamido)(3,4-cyclopenta(/)phenanthren-2-yl)dimethylsilanetitanium    1,4-diphenyl-1,3-butadiene.

Bis(L) containing complexes including bridged complexes suitable for usein the present invention include:

-   biscyclopentadienylzirconiumdimethyl,-   biscyclopentadienyltitaniumdiethyl,-   biscyclopentadienyltitaniumdiisopropyl,-   biscyclopentadienyltitaniumdiphenyl,-   biscyclopentadienylzirconium dibenzyl,-   biscyclopentadienyltitanium-2,4-pentadienyl,-   biscyclopentadienyltitanlummethylmethoxide,-   biscyclopentadienyltitaniummethylchloride,-   bispentamethylcyclopentadienyltitaniumdimethyl,-   bisindenyltitaniumdimethyl,-   indenylfluorenyltitaniumdiethyl,-   bisindenyltitaniummethyl(2-(dimethylamino)benzyl),-   bisindenyltitanium methyltrimethylsilyl,-   bistetrahydroindenyltitanium methyltrimethylsilyl,-   bispentamethylcyclopentadienyltitaniumdiisopropyl,-   bispentamethylcyclopentadienyltitaniumdibenzyl,-   bispentamethylcyclopentadienyltitaniummethylmethoxide,-   bispentamethylcyclopentadienyltitaniummethylchloride,-   (dimethylsilyl-bis-cyclopentadienyl)zirconiumdimethyl,-   (dimethylsilyl-bis-pentamethylcyclopentadienyl)titanium-2,4-pentadienyl,-   (dimethylsilyl-bis-t-butylcyclopentadienyl)zirconiumdichloride,-   (methylene-bis-pentamethylcyclopentadienyl)titanium(III)    2-(dimethylamino)benzyl,-   (dimethylsilyl-bis-indenyl)zirconiumdichloride,-   (dimethylsilyl-bis-2-methylindenyl)zirconiumdimethyl,-   (dimethylsilyl-bis-2-methyl-4-phenylindenyl)zirconiumdimethyl,-   (dimethylsilyl-bis-2-methylindenyl)zirconium-1,4-diphenyl-1,3-butadiene,-   (dimethylsilyl-bis-2-methyl-4-phenylindenyl)zirconium (II)    1,4-diphenyl-1,3-butadiene,-   (dimethylsilyl-bis-tetrahydroindenyl)zirconium(II)    1,4-diphenyl-1,3-butadiene,-   (dimethylsilyl-bis-fluorenyl)zirconiumdichloride,-   (dimethylsilyl-bis-tetrahydrofluorenyl)zirconiumdi(trimethylsilyl),-   (isopropylidene)(cyclopentadienyl)(fluorenyl)zirconiumdibenzyl, and-   (dimethylsilylpentamethylcyclopentadienylfluorenyl)zirconiumdimethyl.    Concerning the Cocatalyst

The metal complexes are rendered catalytically active by combinationwith an activating cocatalyst or by use of an activating technique.Suitable activating cocatalysts for use herein include neutral Lewisacids, such as C ₁₋₃₀ hydrocarbyl substituted Group 13 compounds,especially tri(hydrocarbyl)aluminum- or tri(hydrocarbyl)boron compoundsand halogenated (including perhalogenated) derivatives thereof, havingfrom 1 to 20 carbons in each hydrocarbyl or halogenated hydrocarbylgroup, more especially perfluorinated tri(aryl)boron compounds, and mostespecially tris(pentafluorophenyl)borane; nonpolymeric, compatible,noncoordinating, ion forming compounds (including the use of suchcompounds under oxidizing conditions), especially the use of ammonium-,phosphonium-, oxonium-, carbonium-, silylium-, sulfonium-, orferrocenium-salts of compatible, noncoordinating anions; bulkelectrolysis (explained in more detail hereinafter); and combinations ofthe foregoing activating cocatalysts and techniques. The foregoingactivating cocatalysts and activating techniques have been previouslytaught with respect to different metal complexes in the followingreferences: U.S. Pat. Nos. 5,132,380, 5,153,157, 5,064,802, 5,321,106,5,721,185,5,350,723, and 5,919,983.

Combinations of Lewis acids, especially the combination of a trialkylaluminum compound having from 1 to 4 carbons in each alkyl group and ahalogenated tri(hydrocarbyl)boron compound-having from 1 to 20 carbonsin each hydrocarbyl group, especially tris(pentafluorophenyl)borane,further combinations of such neutral Lewis acid mixtures with apolymeric or ollgomeric alumoxane, and combinations of a single neutralLewis acid, especially tris(pentafluoro-phenyl)borane with a polymericor oligomeric alumoxane are desirable activating catalysts.

Suitable ion forming compounds useful as cocatalysts in one embodimentof the present invention comprise a cation which is a Bronsted acidcapable of donating a proton, and a compatible, noncoordinating anion,A⁻. As used herein, the term “noncoordinating” means an anion orsubstance which either does not coordinate to the Group 4 metalcontaining precursor complex and the catalytic derivative derivedtherefrom, or which is only weakly coordinated to such complexes therebyremaining sufficiently labile to be displaced by a Lewis bases such asolefin monomer. A noncoordinating anion specifically refers to an anionwhich when functioning as a charge balancing anion in a cationic metalcomplex does not transfer an anionic substituent or fragment thereof tosaid cation thereby forming neutral complexes. “Compatible anions” areanions which are not degraded to neutrality when the initially formedcomplex decomposes and are Noninterfering with desired subsequentpolymerization or other uses of the complex.

Preferred anions are those containing a single coordination complexcomprising a charge-bearing metal or metalloid core which anion iscapable of balancing the charge of the active catalyst species (themetal cation) which may be formed when the two components are combined.Also, said anion should be sufficiently labile to be displaced byolefinic, diolefinic and acetylenically unsaturated compounds or otherneutral Lewis bases such as ethers or nitriles. Suitable metals include,but are not limited to, aluminum, gold and platinum. Suitable metalloidsinclude, but are not limited to, boron, phosphorus, and silicon.Compounds containing anions which comprise coordination complexescontaining a single metal or metalloid atom are, of course, well knownand many, particularly such compounds containing a single boron atom inthe anion portion, are available commercially.

Preferably such cocatalysts may be represented by the following generalformula:a (L*—H)_(d) ⁺(A′)^(d−)wherein:

-   -   L* is a neutral Lewis base;    -   (L*—H)⁺ is a Bronsted acid;    -   A′^(d−) is a noncoordinating, compatible anion having a charge        of d−, and    -   d is an integer from 1 to 3.

More preferably A′^(d−) corresponds to the formula: [M*Q_(4]) ⁻;

-   -   wherein:    -   M* is boron or aluminum in the +3 formal oxidation state; and    -   Q independently each occurrence is selected from hydride,        dialkylamido, halide, hydrocarbyl, halohydrocarbyl, halocarbyl,        hydrocarbyloxide, hydrocarbyloxy substituted-hydrocarbyl,        organometal substituted-hydrocarbyl, organometalloid        substituted-hydrocarbyl halohydrocarbyloxy, halohydrocarbyloxy        substituted hydrocarbyl, halocarbyl-substituted hydrocarbyl, and        halo-substituted silylhydrocarbyl radicals (including        perhalogenated hydrocarbyl-p rhalogenated hydrocarbyloxy- and        perhalogenated silylhydrocarbyl radicals), said Q having up to        20 carbons with the proviso that in not more than one occurrence        is Q halide. Examples of suitable hydrocarbyloxide Q groups are        disclosed in U.S. Pat. No. 5,296,433.

In a more preferred embodiment, d is one, that is, the counter ion has asingle negative charge and is A″. Activating cocatalysts comprisingboron which are particularly useful in the preparation of catalysts ofthis invention may be represented by the following general formula:(L*—H)⁺(BQ₄)⁻;wherein:

-   -   L* is as previously defined;    -   B is boron in a formal oxidation state of 3; and    -   Q is a hydrocarbyl-, hydrocarbyloxy-, fluorinated hydrocarbyl-,        fluorinated hydrocarbyloxy-, or fluorinated        silylhydrocarbyl-group of up to 20 nonhydrogen atoms, with the        proviso that in not more than one occasion is Q hydrocarbyl.

Most preferably, Q is each occurrence a fluorinated aryl group,especially, a pentafluorophenyl group.

Illustrative, but not limiting, examples of boron compounds which may beused as an activating cocatalyst in the preparation of the improvedcatalysts of this invention are tri-substituted ammonium salts such as:

-   trimethylammonium tetraphenylborate,-   methyldioctadecylammonium tetraphenylborate,-   triethylammonium tetraphenylborate,-   tripropylammonium tetraphenylborate,-   tri(n-butyl)ammonium tetraphenylborate,-   methyltetradecyloctadecylammonium tetraphenylborate,-   N,N-dimethylanilinium tetraphenylborate,-   N,N-diethylanilinium tetraphenylborate,-   N,N-dimethyl(2,4,6-trimethylanilinium) tetraphenylborate,-   trimethylammonium tetrakis(pentafluorophenyl)borate,-   methylditetradecylammonium tetrakis(pentafluorophenyl)borate,-   methyldioctadecylammonium tetrakis(pentafluorophenyl)borate,-   triethylammonium tetrakis(pentafluorophenyl)borate,-   tripropylammonium tetrakis(pentafluorophenyl)borate,-   tri(n-butyl)ammonium tetrakis(pentafluorophenyl)borate,-   tri(sec-butyl)ammonium tetrakis(pentafluorophenyl)borate,-   N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate,-   N,N-diethylanilinium tetrakis(pentafluorophenyl)borate,-   N,N-dimethyl(2,4,6-trimethylanilinium)    tetrakis(pentafluorophenyl)borate,-   trimethylammonium tetrakis(2,3,4,6-tetrafluorophenyl)borate,-   triethylammonium tetrakis(2,3,4,6-tetrafluorophenyl)borate,-   tripropylammonium tetrakis(2,3,4,6-tetrafluorophenyl)borate,-   tri(n-butyl)ammonium tetrakis(2,3,4,6-tetrafluorophenyl)borate,-   dimethyl(t-butyl)ammonium tetrakis(2,3,4,6-tetrafluorophenyl)borate,-   N,N-dimethylanilinium tetrakis(2,3,4,6-tetrafluorophenyl)borate,-   N,N-diethylanilinium tetrakis(2,3,4,6-tetrafluorophenyl)borate, and-   N,N-dimethyl-(2,4,6-trimethylanilinium)    tetrakis-(2,3,4,6-tetrafluorophenyl)borate.

Dialkyl ammonium salts such as:

-   dioctadecylammonium tetrakis(pentafluorophenyl)borate,-   ditetradecylammonium tetrakis(pentafluorophenyl)borate, and-   dicyclohexylammonium tetrakis(pentafluorophenyl)borate.

Tri-substituted phosphonium salts such as:

-   triphenylphosphonium tetrakis(pentafluorophenyl)borate,-   methyldioctadecylphosphonium tetrakis(pentafluorophenyl)borate, and-   tri(2,6-dimethylphenyl)phosphonium    tetrakis(pentafluorophenyl)borate.

Especially preferred are tetrakis(pentafluorophenyl)borate salts of longchain alkyl mono- and disubstituted ammonium complexes, especiallyC₁₄-C₂₀ alkyl ammonium complexes, especially methyldi(octadecyl)ammoniumtetrakis(pentafluorophenyl)borate and methyldi(tetradecyl)-ammoniumtetrakis(pentafluorophenyl)borate, or mixtures including the same Suchmixtures include protonated ammonium cations derived from aminescomprising two C₁₄, C₁₆ or C₁₈ alkyl groups and one methyl group. Suchamines are available from Witco Corp., under the trade name Kemamine™T9701, and from Akzo-Nobel under the trade name Armeen™ M2HT.

Another suitable ammonium salt; especially for use in heterogeneouscatalyst systems is formed upon reaction of a organometal compound,especially a tri(C₁₋₆alkyl)aluminum compound with an ammonium salt of ahydroxyaryltris(fluoroaryl)borate compound. The resulting compound is anorganometaloxyaryltris(fluoroaryl)borate compound which is generallyinsoluble in aliphatic liquids. Typically, such compounds areadvantageously precipitated on support materials, such as silica,alumina or trialkylaluminum passivated silica, to form a supportedcocatalyst mixture. Examples of suitable compounds include the reactionproduct of a tri(C₁₋₆ alkyl)aluminum compound with the ammonium salt ofhydroxyaryltris(aryl)borate. Suitable hydroxyaryltris(aryl)-boratesinclude the ammonium salts, especially the forgoing long chain alkylammonium salts of:

-   (4-dimethylaluminumoxy-1-phenyl)tris(pentafluorophenyl)borate,-   (4-dimethylaluminumoxy-3,5-di(trimethylsilyl)-1-phenyl)tris(pentafluorophenyl)borate,-   (4-dimethylaluminumoxy-3,5-di(t-butyl)-1-phenyl)tris(pentafluorophenyl)borate,-   (4-dimethylaluminumoxy-1-benzyl)tris(pentafluorophenyl)borate,-   (4-dimethylaluminumoxy-3-methyl-1-phenyl)tris(pentafluorophenyl)borate,-   (4-dimethylaluminumoxy-tetrafluoro-1-phenyl)tris(pentafluorophenyl)borate,-   (5-dimethylaluminumoxy-2-naphthyl)tris(pentafluorophenyl)borate,-   4-(4-dimethylaluminumoxy-1-phenyl)phenyltris(pentafluorophenyl)borate,-   4-(2-(4-(dimethylaluminumoxyphenyl)propane-2-yl)phenyloxy)tris(pentafluorophenyl)borate,-   (4-diethylaluminumoxy-1-phenyl)tris(pentafluorophenyl)borate,-   (4-diethylaluminumoxy-3,5-di(trimethylsilyl)-1-phenyl)tris(pentafluorophenyl)borate,-   (4-diethylaluminumoxy-3,5-di(t-butyl)-1-phenyl)tris(pentafluorophenyl)borate,-   (4-diethylaluminumoxy-1-benzyl)tris(pentafluorophenyl)borate,-   (4-diethylaluminumoxy-3-methyl-1-phenyl)tris(pentafluorophenyl)borate,-   (4-diethylaluminumoxy-tetrafluoro-1-phenyl)tris(pentafluorophenyl)borate,-   (5-diethylaluminumoxy-2-naphthyl)tris(pentafluorophenyl)borate,-   4-(4-diethylaluminumoxy-1-phenyl)phenyltris(pentafluorophenyl)borate,-   4-(2-(4-(diethylaluminumoxyphenyl)propane-2-yl)phenyloxy)tris(pentafluorophenyl)borate,-   (4-diisopropylaluminumoxy-1-phenyl)tris(pentafluorophenyl)borate,-   (4-diisopropylaluminumoxy-3,5-di(trimethylsilyl)-1-phenyl)tris(pentafluorophenyl)borate,-   (4-diisopropylaluminumoxy-3,5-di(t-butyl)-1-phenyl)tris(pentafluorophenyl)borate,-   (4-diisopropylaluminumoxy-1-benzyl)tris(pentafluorophenyl)borate,-   (4-diisopropylaluminumoxy-3-methyl-1-phenyl)tris(pentafluorophenyl)borate,-   (4-diisopropylaluminumoxy-tetrafluoro-1-phenyl)tris(pentafluorophenyl)borate,-   (5-diisopropylaluminumoxy-2-naphthyl)tris(pentafluorophenyl)borate,-   4-(4-diisopropylaluminumoxy-1-phenyl)phenyltris(pentafluorophenyl)borate,    and-   4-(2-(4(diisopropylaluminumoxyphenyl)propane-2-yl)phenyloxy)tris(pentafluorophenyl)borate.

An especially preferred ammonium compound is methylditetra-decylammonium(4-diethylaluminumoxy-1-phenyl)tris(penta-fluorophenyl)borate,methyldihexadecylammonium(4-diethylaluminumoxy-1-phenyl)tris(penta-fluorophenyl)borate,methyldioctadecyl-ammonium(4-diethylaluminumoxy-1-phenyl)tris(pentafluorophenyl)borate, andmixtures thereof. The foregoing complexes are disclosed in U.S. Pat.Nos. 5,834,393 and 5,783,512.

Another suitable ion forming, activating cocatalyst comprises a salt ofa cationic oxidizing agent and a noncoordinating, compatible anionrepresented by (13 the formula:(Ox_(θ+))_(d)(A′^(d−))_(e), wherein

-   -   Ox^(θ+) is a cationic oxidizing agent having a charge of e+;    -   e is an integer from 1 to 3; and    -   A′^(d+) and d are as previously defined.

Examples of cationic oxidizing agents include: ferrocenium,hydrocarbyl-substituted ferrocenium, Ag⁺ or Pb⁺. Preferred embodimentsof A′^(d−) are those anions previously defined with respect to theBronsted acid containing activating cocatalysts, especiallytetrakis(pentafluorophenyl)borate.

Another suitable ion forming, activating cocatalyst comprises a compoundwhich is a salt of a carbenium ion and a noncoordinating, compatibleanion represented by the formula:©⁺A′⁻wherein:

-   -   ©⁺ is a C₁₋₂₀ carbenium ion; and    -   A′⁻ is a noncoordinating, compatible anion having a charge of        −1. A preferred carbenium ion is the trityl cation, that is,        triphenylmethylium.

A further suitable ion forming, activating cocatalyst comprises acompound which is a salt of a silyllum ion and a noncoordinating,compatible anion represented by the formula:

R₃Si(X′)A′⁻

wherein:

-   -   R is C₁₋₁₀ hydrocarbyl;    -   X is hydrogen or R; and    -   A″⁻ is as previously defined.

Preferred silylium salt activating cocatalysts are trimethylsilyliumtetrakispentafluorophenylborate, triethylsilyliumtetrakispentafluorophenylborate and ether substituted adducts thereof.Silylium salts have been previously generically disclosed in J. ChemSoc. Chem. Comm., 1993, 383-384, as well as Lambert, J. B., et al.,Organometallics, 1994, 13, 2430-2443. The use of the above silyliumsalts as activating cocatalysts for addition polymerization catalysts isclaimed in U.S. Pat. No. 5,625,087.

Certain complexes of alcohols, mercaptans, silanols, and oximes withtris(pentafluorophenyl)borane are also effective catalyst activators andmay be used according to the present invention. Such cocatalysts aredisclosed in U.S. Pat. No. 5,296,433.

The molar ratio of catalyst/cocatalyst employed preferably ranges from1:10,000 to 10:1, more preferably from 1:5000 to 10:1, most preferablyfrom 1:1000 to 1:1. Tris(pentafluorophenyl)borane, where used as anactivating cocatalyst is preferably employed in a molar ratio to themetal complex of from 0.5:1 to 10:1, more preferably from 1:1 to 6:1most preferably from 1:1 to 5:1. The remaining activating cocatalystsare generally preferably employed in approximately equimolar quantitywith the metal complex. Preferably, the catalyst and activatingcocatalyst are present on the support in an amount of from 5 to 200,more preferably from 10 to 75 micromoles per gram of support.

The catalysts may be used to polymerize ethylenically and/oracetylenically unsaturated monomers having from 2 to 100,000 carbonatoms either alone or in combination. Preferred monomers include theC₂₋₂₀ α-olefins especially ethylene, propylene, isobutylene, 1-butene,1-pentene, 1-hexene, 3-methyl-1-pentene, 4-methyl-1-pentene, 1-octene,1-decene, long chain macromolecular α-olefins, and mixtures thereof.Other preferred monomers include styrene, C₁₋₄ alkyl substitutedstyrene, tetrafluoroethylene, vinylbenzocyclobutane,ethylidenenorbornene, 1,4-hexadiene, 1,7-octadiene, vinylcyclohexane,4-vinylcyclohexene, divinylbenzene, and mixtures thereof with ethylene.Long chain macromolecular aα-olefins are vinyl terminated polymericremnants formed in situ during continuous solution polymerizationreactions. Under suitable processing conditions such long chainmacromolecular units are readily polymerized into the polymer productalong with ethylene and other short chain olefin monomers to give smallquantities of long chain branching in the resulting polymer. Mostpreferably the present metal complexes are used in the polymerization ofpropylene to prepare polypropylene having a high degree of isotacticity.

In general, the polymerization may be accomplished at conditions wellknown in the prior art for Ziegler-Natta or Kaminsky-Sinn typepolymerization reactions, such as temperatures from 0 to 250° C. andpressures from atmospheric to 1000 atmospheres (0.1 to 100 MPa).Suspension, solution, slurry, gas phase or other process conditions maybe employed if desired. The support, if present, is preferably employedin an amount to provide a weight ratio of catalyst (based onmetal):support from 1:100,000 to 1:10, more preferably from 1:50,000 to1:20, and most preferably from 1:10,000 to 1:30. Suitable gas phasereactions may utilize condensation of the monomer or monomers employedin the reaction, or of an inert diluent to remove heat from the reactor.

In most polymerization reactions the molar ratio ofcatalyst:polymerizable compounds employed is from 10⁻¹²:1 to 10⁻¹:1,more preferably from 10⁻¹²:1 to 10⁻⁵:1.

Suitable solvents or diluents for polymerization via a solution orslurry process are noncoordinating, inert liquids. Examples includestraight and branched-chain hydrocarbons such as isobutane, butane,pentane, hexane, heptane, octane, and mixtures thereof; cyclic andallcyclic hydrocarbons such as cyclohexane, cycloheptane,methylcyclohexane, methylcycloheptane, and mixtures thereof;perfluorinated hydrocarbons such as perfluorinated C₄₋₁₀ alkanes, andaromatic and alkyl-substituted aromatic compounds such as benzene,toluene, and xylene. Suitable solvents also include liquid olefins whichmay act as monomers or comonomers including ethylene, propylene,1-butene, butadiene, cyclopentene, 1-hexene, 3-methyl-1-pentene,4-methyl-1-pentene, 1,4-hexadiene, 1,7-octadiene, 1-octene, 1-decene,styrene, divinylbenzene, ethylidenenorbornene, allylbenzene,vinyltoluene (including all isomers alone or in admixture),4-vinylcyclohexene, and vinylcyclohexane. Mixtures of the foregoing arealso suitable.

The catalysts may also be utilized in combination with at least oneadditional homogeneous or heterogeneous polymerization catalyst in thesame or in separate reactors connected in series or in parallel toprepare polymer blends having desirable properties. An example of such aprocess is disclosed in WO 94/00500, as well as U.S. Pat. No. 5,869,575.

Concerning the Support

Preferred supports for use in the present invention include highlyporous silicas, aluminas, aluminosilicates, and mixtures thereof. Themost preferred support material is silica. The support material may bein granular, agglomerated, pelletized, or any other physical form.Suitable materials include, but are not limited to, silicas availablefrom Grace Davison (division of W. R. Grace & Co.) under the designatonsSD 3216.30, Davison Syloid 245, Davison 948 and Davison 952, and from.Crossfield under the designation ES70, and from Degussa AG under thedesignation Aerosil 812; and aluminas available from Akzo Chemicals Inc.under the designation Ketzen Grade B.

Supports suitable for the present invention preferably have a surfacearea as determined by nitrogen porosimetry using the B.E.T. method from10 to 1000 m²/g, and preferably from 100 to 600 m²/g. The pore volume ofthe support, as determined by nitrogen adsorption, advantageously isfrom 0.1 to 3 cm³/g, preferably from _(0.2) to 2 cm³/g. The averageparticle size depends upon the process employed, but typically is from0.5 to 500 μm, preferably from 1 to 100 μm.

Both silica and alumina are known to inherently possess small quantitiesof hydroxyl functionality. When used as a support herein, thesematerials are preferably subjected to a heat treatment and/or chemicaltreatment to reduce the hydroxyl content thereof. Typical heattreatments are carried out at a temperature from 30° C. to 1000° C.(preferably 250° C. to 800° C. for 5 hours or greater) for a duration of0 minutes to 50 hours in an inert atmosphere or air or under reducedpressure, that is, at a pressure of less than 200 Torr. When calcinationoccurs under reduced pressure, preferred temperatures are from 100 to800° C. Residual hydroxy groups are then removed via chemical treatment.Typical chemical treatments include contacting with Lewis acidalkylating agents such as trihydrocarbyl aluminum compounds,trihydrocarbylchlorosilane compounds, trihydrocarbylalkoxysilanecompounds or similar agents.

The support may be functionalized with a silane or chlorosilanefunctionalizing agent to attach thereto pendant silane —(Si—R)═, orchlorosilane —(Si—Cl)═functionality, wherein R is a C₁₋₁₀ hydrocarbylgroup. Suitable functionalizing agents are compounds that react withsurface hydroxyl groups of the support or react with the silicon oraluminum of the matrix; Examples of suitable functionalizing agentsinclude phenylsilane, hexamethyldisilazane diphenylsilane,methylphenylsilane, dimethylsilane, diethylsilane, dichlorosilane, anddichlorodimethylsilane. Techniques for forming such functionalizedsilica or alumina compounds were previously disclosed in U.S. Pat. Nos.3,687,920 and 3,879,368.

In the alternative, the functionalizing agent may be an aluminumcomponent selected from an alumoxane or an aluminum compound of theformula AIR¹ _(x′)R² _(y′), wherein R¹ independently each occurrence ishydride or R, R² is hydride, R or OR, x′ is 2 or 3, y′ is 0 or 1 and thesum of x′ and y′ is 3. Examples of suitable R¹ and R² groups includemethyl, methoxy, ethyl, ethoxy, propyl (all isomers), propoxy (allisomers), butyl (all isomers), butoxy (all isomers), phenyl, phenoxy,benzyl, and benzyloxy. Preferably, the aluminum component is selectedfrom the group consisting of aluminoxanes and tri(C₁₋₄hydrocarbyl)aluminum compounds. Most preferred aluminum components arealuminoxanes, trimethylaluminum, triethylaluminum, tri-isobutylaluminum,and mixtures thereof.

Such treatment typically occurs by:

-   -   (a) adding to the calcined silica sufficient solvent to achieve        a slurry;    -   (b) adding to the slurry the agent in an amount of 0.1 to 5 mmol        agent per gram of calcined silica, preferably 1 to 2.5 mmol        agent per gram of calcined silica to form a treated support;    -   (c) washing the treated support to remove-unreacted agent to        form a washed support, and    -   (d) drying the washed support by heating and/or by subjecting to        reduced pressure.

Alumoxanes (also referred to as aluminoxanes) are oligomeric orpolymeric aluminum oxy compounds containing chains of alternatingaluminum and oxygen atoms, whereby the aluminum carries a substituent,preferably an alkyl group. The structure of alumoxane is believed to berepresented by the following general formulae (—Al(R)—O)_(m′), for acyclic alumoxane, and R₂Al—O(—Al(R)—O)_(m′)—AIR₂, for a linear compound,wherein R is as previously defined, and m′ is an integer ranging from 1to 50, preferably at least 4. Alumoxanes are typically the reactionproducts of water and an aluminum alkyl, which in addition to an alkylgroup may contain halide or alkoxide groups. Reacting several differentaluminum alkyl compounds, such as for example trimethyl aluminum andtri-isobutyl aluminum, with water yields so-called modified or mixedalumoxanes. Preferred alumoxanes are methylalumoxane and methylalumoxanemodified with minor amounts of C₂₋₄ alkyl groups, especially isobutyl.Alumoxanes generally contain minor to substantial amounts of startingaluminum alkyl compound.

Particular techniques for the preparation of alumoxane type compounds bycontacting an aluminum alkyl compound with an inorganic salt containingwater of crystallization are disclosed in U.S. Pat. No. 4,542,119. In aparticular preferred embodiment an aluminum alkyl compound is contactedwith a regeneratable water-containing substance such as hydratedalumina, silica or other substance. This is disclosed in EP-A-338,044.Thus the alumoxane may be incorporated into the support by reaction of ahydrated alumina or silica material, which has optionally beenfunctionalized with silane, siloxane, hydrocarbyloxysilane, orchlorosilane groups, with a tri (C₁₋₁₀ alkyl) aluminum compoundaccording to known techniques.

Additionally, alumoxane may be generated in situ by contacting silica oralumina or a moistened silica or alumina with a trialkyl aluminumcompound optionally in the presence of an inert diluent. Such a processis well known in the art, having been disclosed in EP-A-250,600; U.S.Pat. No. 4,912,075; and U.S. Pat. No. 5,008,228. Suitable allphatichydrocarbon diluents include pentane, isopentane, hexane, heptane,octane, isooctane, nonane, isononane, decane, cyclohexane,methylcyclohexane and combinations of two- or more of such diluents.Suitable aromatic hydrocarbon diluents are benzene, toluene, xylene, andother alkyl or halogen substituted aromatic compounds. Most preferably,the diluent is an aromatic hydrocarbon, especially toluene. Afterpreparation in the foregoing manner the residual hydroxyl contentthereof is desirably reduced to a level less than 2 mmol of OH per gramof support by any of the previously disclosed techniques.

The support, as calcined and as reacted with a functionalizing agent, isreferred to herein as a “support precursor”. The support precursor, towhich the first solution of either the metal complex or the cocatalystin a compatible solvent has been applied and from which the compatiblesolvent is optionally removed, is referred to herein as a “supportedprocalalyst.” The supported procatalyst, to which the second solution ofthe other of metal complex or the cocatalyst in a compatible solvent hasbeen applied and from which the compatible solvent is optionallyremoved, is referred to herein as a “supported catalyst.” The supportprecursor, the supported procatalyst, and the supported catalyst willadvantageously have a pore volume, as determined by nitrogen adsorption,which is from 0.1 to 3 cm³/g, preferably from 0.2 to 2 cm³1/g.

The process for preparing the supported catalyst system of the inventionis advantageous, in that the catalyst and cocatalyst are not mixed priorto depositing them on the support. This accords the catalyst system withimproved stability during the preparation process.

The process of the invention is further advantageous in that itminimizes the use of solvent in the deposition step. This minimizes anycatalyst deactivation caused by exposure to elevated temperatures and/orvacuum, or by incomplete solvent removal. This also translates toeconomic advantages attributable to reduced solvent handling.

In one preferred embodiment of the invention, a sequential doubleimpregnation technique in employed. In particular, in this preferredembodiment of the invention, the support precursor is sequentiallycontacted by a first solution of either the metal complex or thecocatalyst, and thereafter by a second solution of the other of themetal complex or the cocatalyst in each of the two contacting steps, thecontacting solution will be provided in an amount such that 100 percentof the pore volume of the support precursor is at no time exceeded.Optionally, the support precursor may be dried to remove compatiblesolvent after the contacting with the first solution. This feature,however, is not required, provided the solid remains as a dry,free-flowing powder. This embodiment is advantageous, in that batchreactor experiments suggest that it leads to a catalyst exhibiting animproved kinetic profile and a lower exotherm than a catalyst preparedby slurrying the support precursor in a solution of both the metalcomplex and the cocatalyst.

In another preferred embodiment of the invention, the support precursoris slurried in a first solution of the metal complex or the cocatalystto form a supported procatalyst. Sufficient compatible solvent isremoved from the supported procatalyst to result in a recoveredsupported procatalyst which is free-flowing, that is, wherein the amountof compatible solvent is less than 100 percent of the pore volume of thesupport precursor. Thereafter, the recovered supported procatalyst iscontacted with a second solution of the other of the metal complex andcocatalyst, whereupon the second solution is provided in an amount lessthan 100 percent of the pore volume of the support precursor, whereupona supported catalyst system is formed. As the amount of the secondsolution is insufficient to render the supported catalyst system notfree-flowing, an additional solvent removal step is unnecessary.However, if it is desired, compatible solvent may be more fully removedby application of heat, reduced pressure, or a combination thereof. In aparticularly preferred embodiment, the metal complex will be applied inthe first solution, and the cocatalyst will be applied in the secondsolution, particularly when the cocatalyst is easily degraded by theapplication of heat and/or vacuum during drying.

In the case of each of these preferred embodiments, and particularly inthe case of the double impregnation technique, sufficient mixing shouldbe conducted to ensure that the metal complex and cocatalyst areuniformly distributed within the pores of the support precursor, and toensure that the support precursor remains free-flowing. Some exemplarymixing devices include rotating batch blenders, single-cone blenders,double-cone blenders, and vertical conical dryers.

In the case of each of these preferred embodiments, the applicants havefound them to be advantageous in the preparation of preferred catalystsystems wherein the cocatalyst is heat sensitive. Catalyst systemscomprising such heat sensitive cocatalysts have been found to degradeupon application of heat over a period of time sufficient to remove thelarge amounts of compatible solvent normally associated with slurryingtechniques.

While not wishing to be bound by theory, the supported catalyst systemsof the invention may contain a mixture of a single site constrainedgeometry or metallocene complex and activator, rather than or inaddition to the active species. Once in the reactor at highertemperature and/or in the presence of monomer, additional sites maybecome active. Thus, catalysts with lower exotherms and increasing ratesof polymerization (rising kinetic profile) may be prepared, which maylead to improved performance in the polymerization reactor and improvedpolymer morphology.

In the formation of the first and second solutions utilized in theprocess of the invention, exemplary compatible solvents includealiphatic and aromatic hydrocarbons, such as hexane, heptane, ISOPAR™Emixed aliphatic hydrocarbon mixture (available from Exxon ChemicalCompany), and toluene. Such a compatible solvent will be selected inpart on the basis of the solubility of the metal complex or cocatalystto be dissolved therein, as will be evident to one skilled in the art.

As set forth above, it may be desirable during the process to removecompatible solvent (after the applying of the first solution and/brafter the applying of the second solution) to ensure that the amount ofsolvent present does not exceed the pore volume of the supportprecursor. As stated above, minimum solvent translates to greaterstability during drying, particularly in the case of heat sensitivemetal complexes and/or cocatalysts, as well as handling benefitsassociated with the production of a free-flowing material, as opposed toan agglomerated mass. Such solvent removal will be achieved by applyingto the slurry a vacuum of from 0.05 to 150 Torr, preferably from 0.05 to40 Torr and/or by heating the slurry to a temperature of from 0 to 60°C., preferably from 20 to 40° C., with the understanding that when avacuum is applied, any temperature of heating may be correspondinglyreduced.

Concerning the Presence of Scavengers

The supported catalysts of the invention may also be used in combinationwith a tri(hydrocarbyl)aluminum compound having from 1 to 10 carbons ineach hydrocarbyl group, an oligomeric or polymeric alumoxane compound, adi(hydrocarbyl)(hydrocarbyloxy)aluminum compound having from 1 to 10carbons in each hydrocarbyl or hydrocarbyloxy group, or a mixture of theforegoing compounds, if desired. These aluminum compounds are usefullyemployed for their beneficial ability to scavenge impurities such asoxygen, water, and aldehydes from the polymerization mixture. Preferredaluminum compounds include C₂₋₆ trialkyl aluminum compounds, especiallythose wherein the alkyl groups are ethyl, propyl, isopropyl, n-butyl,isobutyl, pentyl, neopentyyl, or-isopentyl, and methylalumoxane modifiedmethylalumoxane and diisobutylalumoxane.

Catalyst:Cocatalyst Ratios

The molar ratio of catalyst/cocatalyst employed ranges from 1; 1000 to1:10, preferably ranges from 1:10 to 1:1, more preferably from 1:5 to1:1. Mixtures of catalysts or activating cocatalysts may also beemployed if desired.

Concerning Polymerizable Monomers

The catalysts, whether or not supported, in any of the processes of thisinvention; whether gas phase, solution, slurry, or any otherpolymerization process, may be used to polymerize addition polymerizablemonomers include ethylenically unsaturated monomers, acetyleniccompounds, conjugated or nonconjugated dienes, polyenes, and mixturesthereof. Preferred monomers include olefins, for example α-olefinshaving from 2 to 100,000, preferably from 2 to 30, more preferably from2 to 8 carbon atoms and combinations of two or more of such α-olefins.

Particularly suitable α-olefins include, for example, ethylene,propylene, 1-butene, 1-pentene, 4-methylpentene-1,1-hexene, 1-heptene,1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene,1-tetradecene, 1-pentadecene, and C₁₆-C₃₀ α-olefins or combinationsthereof, as well as long chain vinyl terminated oligomeric or polymericreaction products formed during the polymerization. Preferably, theα-olefins are ethylene, propene, 1-butene, 4-methyl-pentene-1, 1-hexene,1-octene, and combinations of ethylene and/or propene with one or moreof such other α-olefins. Other preferred monomers include styrene, halo-or alkyl substituted styrenes, tetrafluoroethylene, vinylcyclobutene,1,4-hexadiene, dicyclopentadiene, ethylidene norbornene, and1,7-octadiene. Mixtures of the abovementioned monomers may also beemployed.

A preferred group of olefin comonomers for polymerizations whereethylene is the monomer includes propene, 1-butene, 1-pentene,4-methyl-1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene,1,7-octadiene, 1,5-hexadiene, 1,4-pentadiene, 1,9-decadiene,ethylidenenorbornene, styrene, or a mixture thereof. For polymerizationswherein propene is the monomer, the preferred comonomers are the same asthat immediately previous, but with the inclusion of ethylene instead ofpropene.

Concerning the Presence of Long Chain Branching

Long chain macromolecular α-olefin can be vinyl terminated polymericremnants formed in situ during the practice of the polymerizationprocess of this invention. Under suitable processing conditions suchlong chain macromolecular units may be polymerized into the polymerproduct along with ethylene and other short chain olefin monomers togive small quantities of long chain branching in the resulting polymer.In a preferred embodiment of the invention, the resultant polymers willbe characterized as being substantially linear polymers, as describedand claimed in U.S. Pat. Nos. 5,272,236, 5,278,272, and 5,665,800.

General Polymerization Conditions

In general, the polymerization may be accomplished at conditions wellknown in the prior art for Ziegler-Natta or Kaminsky-Sinn typepolymerization reactions. Suspension, solution, slurry, gas phase orhigh pressure, whether employed in batch or continuous form or otherprocess conditions, may be employed if desired. Examples of such wellknown polymerization processes are depicted in WO 88/02009, U.S. Pat.Nos. 5,084,534; 5,405,922; 4,588,790; 5,032,652; 4,543,399; 4,564,647;4,522.987, and elsewhere. Preferred polymerization temperatures are from0 to 250° C. Preferred polymerization pressures are from 2×10⁵ to 1×10⁷Pa.

The process of the present invention can be employed to advantage in thegas phase copolymerization of olefins. Gas phase processes for thepolymerization of olefins, especially the homopolymerization andcopolymerization of ethylene and propylene, and the copolymerization ofethylene with higher α-olefins such as, for example, 1-butene, 1-hexene,4-methyl-1-pentene are well known in the art. Such processes are usedcommercially on a large scale for the manufacture of high densitypolyethylene (HDPE), medium density polyethylene (MDPE), linear lowdensity polyethylene (LLDPE) and polypropylene.

The gas phase process employed can be, for example, of the type whichemploys a mechanically stirred bed or a gas fluidized bed as thepolymerization reaction zone. Preferred is the process wherein thepolymerization reaction is carried out in a vertical cylindricalpolymerization reactor containing a fluidized bed of polymer particlessupported above a perforated plate, the fluidization grid, by a flow offluidization gas.

The gas employed to fluidize the bed comprises the monomer or monomersto be polymerized, and also serves as a heat exchange medium to removethe heat of reaction from the bed. The hot gases emerge from the top ofthe reactor, normally via a tranquilization zone, also known as avelocity reduction zone, having a wider diameter than the fluidized bedand wherein fine particles entrained in the gas stream have anopportunity to gravitate back into the bed. It can also be advantageousto use a cyclone to remove ultra-fine particles from the hot gas stream.The gas is then normally recycled to the bed by means of a blower orcompressor and a one or more heat exchangers to strip the gas of theheat of polymerization.

A preferred method of cooling of the bed, in addition to the coolingprovided by the cooled the recycle gas, is to feed a volatile liquid tothe bed to provide an evaporative cooling effect. The volatile liquidemployed in this case can be, for example, a volatile inert liquid, forexample, a saturated hydrocarbon having 3 to 8, preferably 4 to 6,carbon atoms. In the case that the monomer or comonomer itself is avolatile liquid, or can be condensed to provide such a liquid, this canbe suitably be fed to the bed to provide an evaporative cooling effect.Examples of olefin monomers which can be employed in this manner areolefins containing 3 to 8, preferably 3 to 6 carbon atoms. The volatileliquid evaporates in the hot fluidized bed to form gas which mixes withthe fluidizing gas. If the volatile liquid is a monomer or comonomer, itwill undergo some polymerization in the bed. The evaporated liquid thenemerges from the reactor as part of the hot recycle gas, and enters thecompression/heat exchange part of the recycle loop. The recycle gas iscooled in the heat exchanger and, if the temperature to which the gas iscooled is below the dew point, liquid will precipitate from the gas.This liquid is desirably recycled continuously to the fluidized bed. Itis possible to recycle the precipitated liquid to the bed as liquiddroplets carried in the recycle gas stream. This type of process isdescribed, for example, in EP 89691; U.S. Pat. No. 4,543,399; WO94/25495 and U.S. Pat. No. 5,352,749. A particularly preferred method ofrecycling the liquid to the bed is to separate the liquid from therecycle gas stream and to reinject this liquid directly into the bed,preferably using a method which generates fine droplets of the liquidwithin the bed. This type of process is described in BP Chemicals' WO94/28032.

The polymerization reaction occurring in the gas fluidized bed iscatalyzed by the continuous or semi-continuous addition of catalyst.Such catalyst can be supported on an inorganic or organic supportmaterial as described above. The catalyst can also be subjected to aprepolymerization step, for example, by polymerizing a small quantity ofolefin monomer in a liquid inert diluent, to provide a catalystcomposite comprising catalyst particles embedded in olefin polymerparticles.

The polymer is produced directly in the fluidized bed by catalyzedcopolymerization of the monomer and one or more comonomers on thefluidized particles of catalyst, supported catalyst or prepolymer withinthe bed. Start-up of the polymerization reaction is achieved using a bedof preformed polymer particles, which are preferably similar to thetarget polyolefin, and conditioning the bed by drying with inert gas ornitrogen prior to introducing the catalyst, the monomers and any othergases which it is desired to have in the recycle gas stream, such as adiluent gas, hydrogen chain transfer agent, or an inert condensable gaswhen operating in gas phase condensing mode. The produced polymer isdischarged continuously or discontinuously from the fluidized bed asdesired.

The gas phase processes suitable for the practice of this invention arepreferably continuous processes which provide for the continuous supplyof reactants to the reaction zone of the reactor and the removal ofproducts from the reaction zone of the reactor, thereby providing asteady-state environment on the macro scale in the reaction zone of thereactor.

Typically, the fluidized bed of the gas phase process is operated attemperatures greater than 50° C., preferably from 60° C. to 110° C.,more preferably from 70° C. to 110° C.

Typically the molar ratio of comonomer to monomer used in thepolymerization depends upon the desired density for the compositionbeing produced and is 0.5 or less desirably, when producing materialswith a density range of from 0.91 to 0.93 the comonomer to monomer ratiois less than 0.2, preferably less than 0.05, even more preferably lessthan 0.02, and may even be less than 0.01. Typically, the ratio ofhydrogen to monomer is less than 0.5, preferably less than 0.2, morepreferably less than 0.05, even more preferably less than 0.02 and mayeven be less than 0.01.

The above-described ranges of process variables are appropriate for thegas phase process of this invention and may be suitable for otherprocesses adaptable to the practice of this invention.

A number of patents and patent applications describe gas phase processeswhich are adaptable for use in the process of this invention,particularly, U.S. Pat. Nos. 4,588,790; 4,543,399; 5,352.749; 5,436,304;5,405,922; 5.462,999; 5,461,123; 5.453,471; 5,032.562; 5,028,670;5,473,028; 5,106,804; and EP applications 659,773; 692,500; and PCTApplications WO 94/29032, WO 94/25497, WO 94/25495, WO 94/28032; WO95/13305; WO 94/26793; and WO 95/07942.

Molecular weight control agents can be used in combination with thepresent cocatalysts. Examples of such molecular weight control agentsinclude hydrogen, trialkyl aluminum compounds or other known chaintransfer agents.

EXAMPLES

Unless otherwise stated, all manipulations were carried out in an inertatmosphere either in a nitrogen-filled glove box or under nitrogen usingSchlenk techniques.

Reagents, Rac-ethylene-bis(indenyl)Zr(II) 1,4-diphenyl-1,3-butadiene,henceforward called EBIZr(II), and Rac-ethylenebis(tetrahydroindenyl)Zr(II) 1,4-diphenyl-1,3-butadiene, henceforwardcalled EBTHIZr(II) were prepared as described in U.S. Pat. No.5,527,929, examples 11 and 33, respectively.(t-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium(II) η⁴-3-methyl-1,3-pentadiene, henceforward called CGCTI(II) wasprepared as described in U.S. Pat. No. 5,470,993, example 17.Tris(Pentafluorophenyl)borane was purchased from Boulder Scientific andused without further purification. bis(hydrogenated tallow alkyl)methylammonium tris(pentafluorophenyl)(4-hydroxyphenyl)borate, henceforwardcalled HAHB, was prepared as described in PCT98/27119. ISOPAR™Ehydrocarbon mixture was obtained from Exxon Chemical Company. All othersolvents were purchased from Aldrich Chemical Company as anhydrousreagents and were further purified by a nitrogen purge and by passingthem down a 12 inch column of chunk alumina which had been heat treatedovernight at 250° C.;

Preparation of TEA-treated ES-70 silica. A 200 g sample of CrosfieldES-70 silica was calcined for 4 hours at 500° C. in air, thentransferred to a nitrogen-filled glove box. A 20 g sample of the silicawas slurried in 120 mL hexane, and 30.8 mL of a 1.0 M solution oftriethylaluminum in hexanes was added over several minutes. The slurrywas allowed to stand for 1 hour. At this time, the solids were collectedon a fritted funnel, washed three times with hexanes, and dried invacuo.

Preparation of TEA-treated 948 silica. A 200 sample of Davison 948silica (available from Grace-Davison) was calcined for 4 hours at 250°C. in air, then transferred to a nitrogen-filled glove box. A 15 gsample of the silica was slurried in 90 mL hexane, and 30 mL of a 1.0 Msolution of triethylaluminum in hexane was added over several minutes.The addition rate was slow enough to prevent solvent reflux. The slurrywas agitated on a mechanical shaker for 1 hour. At this time, the solidswere collected on a fritted funnel, washed three times with 50 mLportions of hexanes, and dried in vacuo.

Preparation of Scavenger. ES-70 silica from Crosfield was calcined inair, in a flat tray, at 200° C. for four hours. The calcined silica waspoured into a dry glass bottle and quickly transferred to an inertatmosphere glove box. In the dry box, 30.0 g of the calcined ES-70 wereaccurately weighed into a 500 mL Schlenk flask, and 150 mL of hexanewere added to make a slurry. The flask was fitted with a septum andtaken out of the drybox where 0.90 mL of deionized water were added. Theflask was shaken vigorously, by hand, for a few moments and thenreturned to the drybox. Next, 100 mL of 1 M TEA in hexane were added tothe flask, by syringe, while swirling the flask by hand. The totaladdition time was 5 minutes. The flask was agitated vigorously by handand left to stand for about an hour. The treated silica was filtered ona fritted funnel and washed with several volumes of hexane. The silicawas returned to the Schlenk flask and dried to constant weight undervacuum at ambient temperature.

Agitated Dry-Phase Polymerization Reactions. A 2.5-L stirred, fixed bedautoclave was charged with 300 g dry NaCl, and stirring was begun at 300rpm. The reactor was pressurized to 7 bar ethylene and heated to thepolymerization reaction temperature. 1-hexene and hydrogen wereintroduced to the appropriate ppm concentration, as measured by massed56 and 2 on a mass spectrometer, respectively. A scavenger, prepared asdescribed above, was introduced to the reactor. In a separate vessel,0.1 g of the supported catalyst was mixed with an additional 0.5 g ofthe scavenger. The combined catalyst and scavenger were subsequentlyinjected into the reactor. Ethylene pressure was-maintained on a feed asdemand, and hexene was fed as a liquid to the reactor to maintain theppm concentration. Temperature was regulated by dual heating and coolingbaths. After 90 minutes the reactor was depressurized, and the salt andpolymer were removed via a dump valve. The polymer was washed withcopious distilled water to remove the salt, then dried at 50° C.

Example One Monoimpregnated EBIZr(II)/FAB Catalyst

To 3.0 g of Et₃Al treated ES-70 silica prepared as described above wasadded 8 mL of toluene and 3.20 mL of a 0.037 M ethylene EBIZr(II)solution in toluene. The mixture was dried under vacuum at ambienttemperature until the fluidization of the powder ceased. Two days later,to 1 g of the above powder was added 0.22 mL of a 0.1 M solution oftris(pentafluorophenyl)borane, and the powder was mixed until it washomogenous. The solvent was not dried from the pores of the silica. Fivedays after the tris(pentafluorophenyl)borane addition, the catalyst wastested for olefin polymerization activity as described above with ahexene concentration of 3000 ppm, no added hydrogen, and apolymerization temperature of 70° C. Addition of 0.1 g catalyst resultedin a 16° C. exotherm and a gently decaying kinetic profile with a netefficiency of 40 g/gHrBar over 90 minutes.

Example Two Double Impregnated CGCTI/(II)/HAHB Catalyst

To 2.5 mL of a 0.04 M solution of HAHB in toluene was added 60 μL of a1.9 M Et₃Al solution. The solution was next added to 2.5 g ofEt₃Al-treated Davison 948 silica prepared as described above. Themixture was vigorously agitated to a free flowing powder, then thesolvent was removed under vacuum. Next, 0.5 mL of a 0.2 M solution ofCGCTi(II) in Isopar®E was added to the dry supported cocatalyst. Themixture was again agitated, then the solvent was removed in vacuoyielding a brown-green solid. A 0.1 g sample of the catalyst wasevaluated for polymerization activity as described above with a hexeneconcentration of 3000 ppm and a hydrogen concentration of 800 ppm.Injection of the catalyst resulted in a 5.5° C. exotherm. After theinitial exotherm it had a moderately decaying kinetic profile. The netactivity was 99 g/gHrBar for a 90 minute run.

Example Three Comparative Example of a Slurried and Dried CGCTi(II)/HAHBCatalyst

To 3 mL of a 0.040 M solution of HAHB in toluene was added 70 μL of a1.9 M Et₃Al solution in toluene. This solution was mixed for 30 seconds,then was added to 3.0 g Et₃Al-treated Davison 948 silica prepared asdescribed above in 12 mL toluene. To this slurry was added 0.55 mL of a0.22 M solution of CGCTi(II) in toluene. The combined mixture wasslurried briefly (<1 minute), and the solvent was removed under vacuumto give a free flowing, green/brown solid. A 0.1 g sample of thecatalyst was evaluated for polymerization activity under identicalconditions as described above in example 2. Catalyst injection resultedin a 30° C. exotherm. After the initial exotherm it had steeply decayingkinetic profile. The net activity was 53 g/gHrBar for a 90 minute run.

Example Four Double Impregnated EBIZr(II)/HAHB Catalyst

In an inert atmosphere dry box, 2.0 g of Crosfield ES-70 silica preparedas described above was accurately weighed into a 100 mL schlenk flask.In a separate container, 1.2 mL of 0.081 M HAHB in toluene and 60 μL of1.76 M TEA were together for one minute. The solution was quantitativelytransferred to the silica via syringe, and the silica was agitated to auniform and free flowing powder. The solvent was removed under vacuum atambient temperature until the point of constant weight. Next, 2.5 mL of0.026 M EBIZr(II) solution in toluene were added, and the mixture wasvigorously agitated until the powder was uniform and free flowing. Thesolvent was removed under vacuum at ambient temperature until the pointof constant weight. 2.0 g of red catalyst powder were recovered. A gasphase batch polymerization reaction was carried out at 70° C. asdescribed above with a hexene concentration of 8000 ppm and no addedhydrogen. Injection of 0.1 g of the catalyst resulted in a 7.9° C.exotherm. After the initial exotherm, the reaction proceeded with astable kinetic profile. The net activity was 63 g/gHrBar for a 90 minuterun.

Example Five Double Impregnated EBTHIZr(II)/HAHB Catalyst

In an inert atmosphere glove box, 2.0 g of Crosfield ES-70 silicaprepared as described above were accurately weighed into a 100 mLschlenk flask. In a separate flash, 0.78 mL of a 0.081 M solution ofHAHB in toluene and 40 μL of 1.76 M TEA in toluene were combined. Thesolution was quantitatively transferred to the silica using a syringe,and the silica was agitated until to a uniform and free flowing powder.The solvent was removed under vacuum at ambient temperature until thepoint of constant weight. Next, 25 ml of a 0.017 M solution ofEBTHIZr(II) in toluene was added, and the mixture was vigorouslyagitated to a uniform, free flowing powder. The solvent was removedunder vacuum at ambient temperature until the point of constant weight.A gas phase batch polymerization reaction was carried out at 70° C. asdescribed above with a hexene concentration of 8000 ppm and 850 ppmhydrogen. Injection of 0.05 g of the catalyst resulted in a 5° C.exotherm. After the initial exotherm, the reaction proceeded with astable kinetic profile. The net activity was 130 g/gHrBar for a 90minute run.

1. A process for preparing an olefin polymerization catalyst comprisingthe steps of: A. calcining silica at a temperature of 30 to 1000° C. toform calcined silica, B. reacting the calcined silica with an agentselected from the group consisting of: i. Lewis acid alkylating agents,ii. silane or chlorosilane functionalizing agents, and iii. aluminumcomponents selected from an alumoxane or an aluminum compound of theformula AIR¹ _(x′)R² _(y′), wherein R¹ independently each occurrence ishydride or R, R² is hydride, R or OR, wherein R is a C₁ to C₁₀hydrocarbyl group, x′ is 2 or 3, y′ is 0 or 1 and the sum of x′ and y′is 3, to form a support precursor having a specified pore volume, C.applying to the support precursor a first solution in a compatiblesolvent of one of the following: (1) a complex of a metal of Group 3, 4,or the Lanthanide metals of the Periodic Table of the Elements or (2) acocatalyst selected from the group consisting of non-polymeric,non-oligomeric complexes capable of activating the complex of (C)(1) forthe polymerization of α-olefins and removing the compatible solvent ofthe first solution to form a supported procatalyst; D. applying to thesupported procatalyst a second solution in a compatible solvent of theother of the complex or the cocatalyst of (C) to form a supportedcatalyst, wherein the second solution is provided in an amount such that100 percent of the pore volume of the support precursor is not exceeded;and E. removing the compatible solvent of the second solution from thesupported catalyst to form a recovered supported olefin polymerizationcatalyst.
 2. The process of claim 1, wherein the first solution of (C)is provided in an amount not in excess of 100 percent of the pore volumeof the support precursor, and wherein the compatible solvent of step (C)is removed from the supported procatalyst by heating, subjecting toreduced pressure, or a combination thereof.
 3. The process of claim 1,wherein step (C) further comprises: (i) forming a slurry of the supportprecursor in the compatible solvent, (ii) adding to the slurry, thecomplex of step (C)(1) or the cocatalyst of step (C)(2) to form aprocatalyst slurry, and (iii) removing the compatible solvent from theprocatalsyt slurry to form the supported procatalyst.
 4. The process ofclaim 1, wherein the complex is L_(l)MX_(m)X′_(n)X″_(p), or a dimerthereof wherein: L is an anionic, delocalized, π-bonded group that isbound to M, containing up to 50 non-hydrogen atoms, optionally two Lgroups may be joined together through one or more substituents therebyforming a bridged structure, and further optionally one L may be boundto X through one or more substituents of L; M is a metal of Group 4 ofthe Periodic Table of the Elements in the +2, +3 or +4 formal oxidationstate; X is an optional, divalent substituent of up to 50 non-hydrogenatoms that together with L forms a metallocycle with M; X′ is anoptional neutral Lewis base having up to 20 non-hydrogen atoms; X″ eachoccurrence is a monovalent, anionic moiety having up to 40 non-hydrogenatoms, optionally, two X″ groups may be covalently bound togetherforming a divalent dianionic moiety having both valences bound to M, orform a neutral, conjugated or nonconjugated diene that is π-bonded to M(whereupon M is in the +2 oxidation state), or further optionally one ormore X″ and one or more X′ groups may be bonded together thereby forminga moiety that is both covalently bound to M and coordinated thereto bymeans of Lewis base functionality; l is 1 or 2; m is 0 or 1; n is anumber from 0 to 3; p is an integer from 0 to 3; and the sum, l+m+p, isequal to the formal oxidation state of M.
 5. The process of claim 4,wherein the complex contains two L groups which are linked by a bridginggroup, wherein the bridging group corresponds to the formula (ER*₂)_(x),wherein E is silicon or carbon, R* independently each occurrence ishydrogen or a group selected from silyl, hydrocarbyl, hydrocarbyloxy andcombinations thereof, said R* having up to 30 carbon or silicon atoms,and x is 1 to
 8. 6. The process of claim 4, wherein the complexcorresponds to the formula:

wherein: M is titanium, zirconium or hafnium, in the +2 or +4 formaloxidation state; R³ in each occurrence independently is selected fromthe group consisting of hydrogen, hydrocarbyl, silyl, germyl, cyano,halo and combinations thereof, or adjacent R³ groups together form ahydrocarbadiyl, siladiyl or germadiyl group thereby forming a fused ringsystem, X″ independently each occurrence is an anionic ligand group ofup to 40 non-hydrogen atoms, or two X″ groups together form a divalentanionic ligand group of up to 40 non-hydrogen atoms or together are aconjugated diene having from 4 to 30 non-hydrogen atoms forming aπ-complex with M, whereupon M is in the +2 formal oxidation state, E issilicon or carbon, R* independently each occurrence is hydrogen or agroup selected from silyl, hydrocarbyl, hydrocarbyloxy and combinationsthereof, said R* having up to 30 carbon or silicon atoms, and x is 1 to8.
 7. The process of claim 1, wherein the complex corresponds to theformula:L_(l)MX_(m)X′_(n)X″_(p), or a dimer thereof wherein: L is an anionic,delocalized, n-bonded group that is bound to M, containing up to 50non-hydrogen atoms; M is a metal of Group 4 of the Periodic Table of theElements in the +2, +3 or +4 formal oxidation state; X is a divalentsubstituent of up to 50 non-hydrogen atoms that together with L forms ametallocycle with M; X′ is an optional neutral Lewis base ligand havingup to 20 non-hydrogen atoms; X″ each occurrence is a monovalent, anionicmoiety having up to 20 non-hydrogen atoms, optionally two X″ groupstogether may form a divalent anionic moiety having both valences boundto M or a neutral C₅₋₃₀ conjugated diene, and further optionally X′ andX″ may be bonded together thereby forming a moiety that is bothcovalently bound to M and coordinated thereto by means of Lewis basefunctionality; l is 1 or 2; m is 1; n is a number from 0 to 3; p is aninteger from 1 to 2; and the sum, l+m+p, is equal to the formaloxidation state of M.
 8. The process of claim 7, wherein the complexcorresponds to the formula:

wherein: M is titanium or zirconium in the +2 or +4 formal oxidationstate; R³ in each occurrence independently is selected from the groupconsisting of hydrogen, hydrocarbyl, silyl, germyl, cyano, halo andcombinations thereof, or adjacent R³ groups together form ahydrocarbadiyl, siladiyl or germadiyl group thereby forming a fused ringsystem, each X″ is a halo, hydrocarbyl, hydrocarbyloxy or silyl group,said group having up to 20 non-hydrogen atoms, or two X″ groups togetherform a C₅₋₃₀ conjugated diene; Y is —O—, —S—, —NR*—, —PR*—; and Z isSiR*₂, CR*₂, SiR*₂SiR*₂, CR*₂CR*₂, CR*═CR*, CR*₂SiR*₂, or GeR*₂,wherein: R* independently each occurrence is hydrogen or a groupselected from silyl, hydrocarbyl, hydrocarbyloxy and combinationsthereof, said R* having up to 30 carbon or silicon atoms.
 9. The processof claim 1, wherein the cocatalyst is represented by the formula(L*—H)_(d) ⁺(A′^(d)) wherein: L* is a neutral Lewis base; (L*—H)⁺ is aBronsted acid; A′^(d−) is a noncoordinating, compatible anion having acharge of d−, and d is an integer from 1 to
 3. 10. The process of claim1, wherein the cocatalyst is represented by the formula(L*—H)*(BQ₄)⁻ wherein: L* is a neutral Lewis base; B is boron in aformal oxidation state of 3; and Q is a hydrocarbyl-, hydrocarbyloxy-,fluorinated hydrocarbyl-, fluorinated hydrocarbyloxy-, or fluorinatedsilylhydrocarbly-group of up to 20 nonhydrogen atoms, with the provisothat in not more than one occasion is Q hydrocarbyl.
 11. The process ofclaim 1, wherein the cocatalyst comprises a salt of a cationic oxidizingagent and a noncoordinating, compatible anion represented by the formula(OX^(e+))_(d)(A′^(d−))_(e) wherein Ox^(e+) is a cationic oxidizing agenthaving a charge of e+; e is an integer from 1 to 3; A′^(d) is anoncoordinating, compatible anion having a charge of d−; and d is aninteger from 1 to
 3. 12. The process of claim 1, wherein the cocatalystcomprises a salt of a carbenium ion and a noncoordinating, compatibleanion represented by the formula©⁺A′⁻ wherein: ©⁺ is a C₁₋₂₀ carbenium ion; and A′⁻ is anoncoordinating, compatible anion having a charge of −1.
 13. The processof claim 1, wherein the cocatlyst comprises a compound which is a saltof a silylium ion and a noncoordinating, compatible anion represented bythe formulaR₃Si(X′)A′⁻ wherein: R is C₁₋₁₀ hydrocarbyl; X is hydrogen or R; and A′⁻is a noncoordinating, compatible anion having a charge of −1.
 14. Theprocess of claim 1, wherein the support precursor has a pore volume, asdetermined by nitrogen adsorption, of from 0.1 to 3 cm³/g.
 15. Theprocess of claim 1, wherein the reacting of the calcined silica with theagent comprises: (a) adding to the calcined silica sufficient solvent toachieve a slurry; (b) adding to the slurry the agent in an amount of 0.1to 5 mmol agent per gram of calcined silica, to form a treated support;(c) washing the treated support to remove unreacted agent to form awashed support; and (d) drying the washed support by heating and/or bysubjecting to reduced pressure.
 16. The process of claim 1, wherein thesupport precursor has a residual hydroxyl content of less than 2 mmol ofOH per gram of support precursor.
 17. The process of claim 1, wherein atleast one of the supported procatalyst or the supported catalyst istreated by at least one of the following: a. applying thereto a vacuumof from 0.05 to 150 Torr; or b. heating to a temperature of up to 60° C.18. A process for polymerizing at least one α-olefin monomer comprising:A. preparing a supported catalyst by: i. calcining silica at atemperature of 30 to 1000° C. to form calcined silica, ii reacting thecalcined silica with an agent selected from the group consisting of: (a)Lewis acid alkylating agents, (b) silane or chlorosilane functionalizingagents, and (c) aluminum components selected from an alumoxane or analuminum compound of the formula AIR¹ _(x′)R² _(Y′), wherein R¹independently each occurrence is hydride or R, R² is hydride, R or OR,wherein R is a C₁ to C₁₀ hydrocarbyl group, x′ is 2 or 3, y′ is 0 or 1and the sum of x′ and y′ is 3, to form a support precursor having aspecified pore volume, iii. applying to the support precursor a firstsolution in a compatible solvent of one of the following: (a) a complexof a metal of Group 3, 4, or the Lanthanide metals of the Periodic Tableof the Elements or (b) a cocatalyst selected from the group consistingof non-polymeric, non-oligomeric complexes capable of activating thecomplex of (iii)(a) for the polymerization of α-olefins and removing thecompatible solvent of the first solution to form a supportedprocatalyst; iv. applying to the recovered supported procatalyst asecond solution in a compatible solvent of the other of the complex orcocatalyst of (iii) to form a supported catalyst, wherein the secondsolution is provided in an amount such that 100 percent of the porevolume of the support precursor is not exceeded; and v. removing thecompatible solvent of the second solution from the supported catalyst toform a recovered supported catalyst; B. pressurizing a gas phasepolymerization reactor with the at least one α-olefin monomer to bepolymerized; C. introducing the recovered supported catalyst to the gasphase polymerization reactor; D. activating the recovered supportedcatalyst; and E. recovering polymerized product from the reactor. 19.The process of claim 18, further comprising providing to the reactor atri(hydrocarbyl)aluminum compound having from 1 to 10 carbons in eachhydrocarbyl group, an oligomeric or polymeric alumoxane compound, adi(hydrocarbyl)(hydrocarbyloxy)aluminum compound having from 1 to 10carbons in each hydrocarbyl or hydrocarbyloxy group, or a mixture of theforegoing compounds, wherein such providing occurs either prior to,during, or subsequent to the introduction to the reactor of therecovered supported catalyst.